1. Field of the Invention
The present application relates to IC packages, and more particularly to IC packages with internal heat dissipation structures.
2. Description of the Related Art
FIG. 1 shows a conventional BGA package 10. The conventional BGA package 10 includes a substrate 2, a plurality of conductive vias perforating the substrate 2, a plurality of external connection terminals such as solder balls, an upper conductive layer 12 formed on the upper surface of the substrate 2, a lower conductive layer 14 formed on the lower surface of the substrate 2, a chip mounting adhesive layer (conductive or non-conductive) 4 on the upper conductive layer 12, and a semiconductor chip 6 attached to the chip mounting adhesive layer 4. The substrate 2 includes a dielectric layer 3, a power plane 8, and a ground plane 11. The semiconductor chip 6 is electrically connected to the upper conductive layer 12 by bonding wires 16.
The conductive vias include a plurality of thermal dissipating vias 18, power vias 20, and signal vias 22 perforating the substrate 2. The solder balls include a plurality of thermal dissipating balls 24, power balls 26, and signal balls 28.
The thermal dissipating balls 24 are connected to the ground plane 11 through thermal dissipating vias 18. The thermal dissipating vias 18 are not connected to the power plane 8. As a result, only the ground plane 11 is part of the direct pathways for dissipating heat in the package 10. The power plane 8 is not part of the pathways for dissipating heat in the package 10.